/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.nifi.processors.flume;
import com.google.common.base.Throwables;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableSet;
import org.apache.flume.EventDeliveryException;
import org.apache.flume.EventDrivenSource;
import org.apache.flume.PollableSource;
import org.apache.flume.Source;
import org.apache.flume.channel.ChannelProcessor;
import org.apache.flume.conf.Configurables;
import org.apache.flume.source.EventDrivenSourceRunner;
import org.apache.nifi.annotation.behavior.InputRequirement;
import org.apache.nifi.annotation.behavior.InputRequirement.Requirement;
import org.apache.nifi.annotation.behavior.Restricted;
import org.apache.nifi.annotation.behavior.TriggerSerially;
import org.apache.nifi.annotation.documentation.CapabilityDescription;
import org.apache.nifi.annotation.documentation.Tags;
import org.apache.nifi.annotation.lifecycle.OnScheduled;
import org.apache.nifi.annotation.lifecycle.OnStopped;
import org.apache.nifi.components.PropertyDescriptor;
import org.apache.nifi.components.Validator;
import org.apache.nifi.processor.ProcessContext;
import org.apache.nifi.processor.ProcessSession;
import org.apache.nifi.processor.ProcessSessionFactory;
import org.apache.nifi.processor.ProcessorInitializationContext;
import org.apache.nifi.processor.Relationship;
import org.apache.nifi.processor.exception.ProcessException;
import org.apache.nifi.processor.util.StandardValidators;
import java.util.List;
import java.util.Set;
import java.util.concurrent.atomic.AtomicReference;
/**
* This processor runs a Flume source
*/
@TriggerSerially
@Tags({"flume", "hadoop", "get", "source", "restricted"})
@InputRequirement(Requirement.INPUT_FORBIDDEN)
@CapabilityDescription("Execute a Flume source. Each Flume Event is sent to the success relationship as a FlowFile")
@Restricted("Provides operator the ability to execute arbitrary Flume configurations assuming all permissions that NiFi has.")
public class ExecuteFlumeSource extends AbstractFlumeProcessor {
public static final PropertyDescriptor SOURCE_TYPE = new PropertyDescriptor.Builder()
.name("Source Type")
.description("The component type name for the source. For some sources, this is a short, symbolic name"
+ " (e.g. spooldir). For others, it's the fully-qualified name of the Source class. See the Flume User Guide for details.")
.required(true)
.addValidator(createSourceValidator())
.build();
public static final PropertyDescriptor AGENT_NAME = new PropertyDescriptor.Builder()
.name("Agent Name")
.description("The name of the agent used in the Flume source configuration")
.required(true)
.defaultValue("tier1")
.addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
.build();
public static final PropertyDescriptor SOURCE_NAME = new PropertyDescriptor.Builder()
.name("Source Name")
.description("The name of the source used in the Flume source configuration")
.required(true)
.defaultValue("src-1")
.addValidator(StandardValidators.NON_EMPTY_VALIDATOR)
.build();
public static final PropertyDescriptor FLUME_CONFIG = new PropertyDescriptor.Builder()
.name("Flume Configuration")
.description("The Flume configuration for the source copied from the flume.properties file")
.required(true)
.defaultValue("")
.addValidator(Validator.VALID)
.build();
public static final Relationship SUCCESS = new Relationship.Builder().name("success")
.build();
private List<PropertyDescriptor> descriptors;
private Set<Relationship> relationships;
private volatile Source source;
private final NifiSessionChannel pollableSourceChannel = new NifiSessionChannel(SUCCESS);
private final AtomicReference<ProcessSessionFactory> sessionFactoryRef = new AtomicReference<>(null);
private final AtomicReference<EventDrivenSourceRunner> runnerRef = new AtomicReference<>(null);
private final AtomicReference<NifiSessionFactoryChannel> eventDrivenSourceChannelRef = new AtomicReference<>(null);
@Override
protected void init(final ProcessorInitializationContext context) {
this.descriptors = ImmutableList.of(SOURCE_TYPE, AGENT_NAME, SOURCE_NAME, FLUME_CONFIG);
this.relationships = ImmutableSet.of(SUCCESS);
}
@Override
protected List<PropertyDescriptor> getSupportedPropertyDescriptors() {
return descriptors;
}
@Override
public Set<Relationship> getRelationships() {
return relationships;
}
@OnScheduled
public void onScheduled(final ProcessContext context) {
try {
source = SOURCE_FACTORY.create(
context.getProperty(SOURCE_NAME).getValue(),
context.getProperty(SOURCE_TYPE).getValue());
String flumeConfig = context.getProperty(FLUME_CONFIG).getValue();
String agentName = context.getProperty(AGENT_NAME).getValue();
String sourceName = context.getProperty(SOURCE_NAME).getValue();
Configurables.configure(source,
getFlumeSourceContext(flumeConfig, agentName, sourceName));
if (source instanceof PollableSource) {
source.setChannelProcessor(new ChannelProcessor(
new NifiChannelSelector(pollableSourceChannel)));
source.start();
}
} catch (Throwable th) {
getLogger().error("Error creating source", th);
throw Throwables.propagate(th);
}
}
@OnStopped
public void stopped() {
if (source instanceof PollableSource) {
source.stop();
} else {
EventDrivenSourceRunner runner = runnerRef.get();
if (runner != null) {
runner.stop();
runnerRef.compareAndSet(runner, null);
}
NifiSessionFactoryChannel eventDrivenSourceChannel = eventDrivenSourceChannelRef.get();
if (eventDrivenSourceChannel != null) {
eventDrivenSourceChannel.stop();
eventDrivenSourceChannelRef.compareAndSet(eventDrivenSourceChannel, null);
}
}
sessionFactoryRef.set(null);
}
@Override
public void onTrigger(ProcessContext context, ProcessSessionFactory sessionFactory) throws ProcessException {
if (source instanceof PollableSource) {
super.onTrigger(context, sessionFactory);
} else if (source instanceof EventDrivenSource) {
ProcessSessionFactory old = sessionFactoryRef.getAndSet(sessionFactory);
if (old != sessionFactory) {
if (runnerRef.get() != null) {
stopped();
sessionFactoryRef.set(sessionFactory);
}
runnerRef.set(new EventDrivenSourceRunner());
eventDrivenSourceChannelRef.set(new NifiSessionFactoryChannel(sessionFactoryRef.get(), SUCCESS));
eventDrivenSourceChannelRef.get().start();
source.setChannelProcessor(new ChannelProcessor(
new NifiChannelSelector(eventDrivenSourceChannelRef.get())));
runnerRef.get().setSource(source);
runnerRef.get().start();
}
}
}
@Override
public void onTrigger(final ProcessContext context, final ProcessSession session) throws ProcessException {
if (source instanceof PollableSource) {
PollableSource pollableSource = (PollableSource) source;
try {
pollableSourceChannel.setSession(session);
pollableSource.process();
} catch (EventDeliveryException ex) {
throw new ProcessException("Error processing pollable source", ex);
}
} else {
throw new ProcessException("Invalid source type: " + source.getClass().getSimpleName());
}
}
}